Sheet metal modular wall units

ABSTRACT

THE INVENTION PROVIDES A MODULAR STRUCTURAL MEMBER FORMED FROM A RECTANGULAR SHEET METAL BLANK BENT TO DEFINE A MEDIAL PANEL SECTION FLANKED BY OPPOSITE REARWARDLY EXTENDING MARGINAL SECTIONS. ONE MARGINAL SECTION COMPRISES A TONGUE AND, SPACED REARWARDLY THEREOF, A LATERALLY OUTWARDLY PROJECTING REARWARDLY FACING FLANGE THAT IS OFFSET LATERALLY INWARD A SUBSTANTIAL DISTANCE FROM THE TONGUE. THE OTHER MARGINAL SECTION COMPRISES A GROOVE PORTION LATERALLY OPPOSITE THE TONGUE AND ANOTHER FLANGE, LATERALLY OPPOSITE THE FIRST AND PROJECTING LATERALLY OUTWARDLY BEYOND THE PANEL SECTION. SUCH MEMBERS CAN BE INTERCONNECTED SIDE BY SIDE AS A FACADE FOR A STANDING WALL, OR PAIRS OF THEM CAN BE FASTENED TOGETHER, FLANGES OPPOSED, TO PROVIDE CURTAIN WALL MODULES.

Feb. 23,1971 R. v ARMITAGE 3,564,00

SHEET METAL MODULAR WALL UNITS Filed Dec. 9. 1968 s Sheets-Sheet 1 Feb. 23, 1971 N, A MTA E 3,564,800

SHEET METAL MODULAR WALL UNITS Filed Deb. 9, 1968 3 Sheets-Sheet 2 Feb-23, 1971 AR ITAG 3,564,800

SHEET METAL MODULAR WALL UNITS Filed Dec. 9, 1968 3 Sheets-Sheet s @81 E I O m United States Patent ()lfice 3,554,809 Patented Feb. 23, 1971 ware Filed Dec. 9, 1968, Ser. No. 782,149 Int. Cl. E04b 2/88, 2/28; E04c 2/08 U.S. Cl. 52-394 16 Claims ABSTRACT OF THE DISCLOSURE The invention provides a modular structural member formed from a rectangular sheet metal blank bent to define a medial panel section flanked by opposite rearwardly extending marginal sections. One marginal section comprises a tongue and, spaced rearwardly thereof, a laterally outwardly projecting rearwardly facing flange that is offset laterally inward a substantial distance from the tongue. The other marginal section comprises a groove portion laterally opposite the tongue and another flange, laterally opposite the first and projecting laterally outwardly beyond the panel section. Such members can be interconnected side by side as a facade for a standing wall, or pairs of them can be fastened together, flanges opposed, to provide curtain wall modules.

This invention relates to modular elements particularly intended for the walls of business and commercial buildings, and the invention pertains more specifically to sheet metal modules that can be interlockingl assembled with one another to provide a curtain wall or a facade.

Various types of modular sheet metal wall forming units are known and have come into widespread use. One class of such units, to which the present invention relates, is used for the construction of so-called curtain walls, which comprise such modular units interlockingly connected in sideby-side relationship and secured to a skeleton framework of a building by means of clips or the like, with the interlocked modules forming both the interior and the exterior wall surfaces of the building.

A curtain wall module of this general type is usually in the form of a shell comprised of two sheet metal members, each bent to have a medial panel section flanked by laterally opposite marginal sections. The panel sections of these members, which are in opposing spaced apart relationship in the complete module, respectively provide an exterior face and an interior face, and the space between them is usually filled with insulating material to prevent transfer of heat from one to the other of the members. The marginal sections of the two members provide for fastening them together to form the complete module and also provide for connection of the module with other similar modules that are sidewardly adjacent to it.

Any such modular unit, to be completely satisfactory, must meet a number of important criteria.

For one thing, there should be little or no metal-tometal contact between the two sheet metal members comprising the module, to prevent heat transfer through the module.

It is also important that each module be capable of such connection with its laterally adjoining curtain wall modules that the modules are interlocked with one another and cooperate in forming a wall having substantial strength and resistance to displacement in all directions, and that there is a tortuous path through each joint between modules, with seals across said path at one or more points, so that air cannot leak through the joint even in windy weather.

Desirably, any such module should have such mirrorimage symmetry of its opposite edge portions that either face of the module can be used as its exterior surface, regardless of the orientation of its laterally adjacent similar modules.

Another and very important requirement for any such module is that it lend itself to easy and inexpensive manufacture and be adapted for quick and convenient assembly with other similar modules to form a curtain wall.

While most prior curtain wall modules have met some of these requirements to a greater or lesser degree, none has met all of them. By contrast, it is an object of the present invention to provide a curtain wall module which fully meets all of the criteria just set forth and which, in addition, possesses certain further advantages not heretofore realized.

More specifically, it is among the objects of this invention to provide a curtain wall module of the character described which affords four separate seals across the joint defined by a connected pair of such modules.

Another specific object of this invention is to provide a curtain wall module which comprises a pair of structural members that can be identical with one another, and which is therefore inexpensive to manufacture, and which, moreover, has its opposite edge portions in mirror-imaged symmetry with one another so that either face of the module can be disposed at the exterior of a curtain wall in which it is incorporated, regardless of the orientation of its laterally adjacent modules.

It follows that it is another object of this invention to provide an inexpensive but very satisfactory and versatile curtain wall module, capable of being assembled with other similar modules in a variety of different arrangements to produce any of a number of different architectural effects.

Another and very important object of this invention is to provide a very versatile sheet metal structural member which is capable of being readily secured to a flatwise opposed similar structural member to provide a curtain wall module of the character just described, and which is also capable of use per se, when interlockingly connected with laterally adjacent similar members, to provide an ornamental and protective facade for a standing wall of other than the curtain type.

It is also a specific object of this invention to provide a modular sheet metal structural member of the character described which can be readily formed from a sheet metal blank by means of relatively simple and inexpensive machinery.

With these observations and objects in mind, the manner in which the invention achieves its purpose will be appreciated from the following description and the accompanying drawings. This invention is not limited to the particular structure or method disclosed, and changes can be made therein which lie within the scope of the appended claims without departing from the invention.

The drawings illustrate one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

FIG. 1 is a front perspective view of the upper portion of a curtain wall module embodying the principles of this invention;

FIG. 2 is a fragmentary view in cross section through a joint between a pair of interlockingly connected curtain wall modules of this invention;

FIG. 3 is a view in cross section, on a reduced scale, of a plurality of structural members of this invention that are interlockingly connected with one another and secured to a standing wall to provide an ornamental facade therefor;

FIG. 4 is a View in cross section on a larger scale, illustrating another arrangement of the structural members of this invention to provide a facade; and

FIG. 5 is a composite view showing, in cross section, a pair of structural members of this invention, such as might be assembled with one another to form a curtain wall module, but with one of the members reversed from the position it would have if so assembled with the other, so that the similarities between the two members are readily apparent.

Referring now to the accompanying drawings, the numeral 5 designates generally a curtain wall module embodying the principles of this invention and comprising, in general, a pair of sheet metal structural members 6 that are connected with one another by fasteners 8, and a pair of insulating elements 9 that are sandwiched between the structural members to prevent heat transferring metal-tometal contact between them.

Each of the structural members 6 is formed from a single rectangular sheet metal blank that is bent along lines extending parallel to opposite side edges thereof to define a medial panel section 11 flanked by opposite marginal sections 12 and 13 that extend rearwardly from the panel section. Although for esthetic reasons the panel sections 11 of the two structural members comprising the module 5 may have different configurations, as showns, the members 6 are in all other respects identical to one another, as may be readily seen from FIG. 5.

The opposite marginal sections 12 and 13 of each structural member 6 are complementary to one another, in that the marginal section 13 has a laterally outwardly projecting tongue 14 while the other marginal section 12 has a laterally outwardly opening groove 15 which is laterally opposite the tongue 14. The groove 15 is of course adapted to receive the tongue 14 on a similar laterally adjacent structural member, to interlockingly connect such structural members and thus also connect curtain wall modules which they comprise.

The extremities of the marginal sections 12 and 13 of each structural member 6 comprise rearwardly facing flange means 16 and 17, respectively, by which the structural member can be connected in opposing relation to another similar structural member to form a curtain wall module 5, as illustrated in FIGS. 1 and 2, or can be connected to a standing wall 18 of concrete or the like, as illustrated in FIGS. 3 and 4, to cooperate with other similar members in providing a protective and ornamental facade for the wall.

When a pair of the structural members 6 of this invention are secured together to form a curtain wall module 5, their panel sections 11 are flatwise spaced apart, and the space between them will normally be filled with thermal insulating material (glass wool batts or the like); but for simplicity such insulation has not been shown.

For purposes of example the panel sections 11 of the structural members 6 shown in the accompanying drawings are illustrated with two diiferent cross-sectional configurations. The panel sections having one of these configurations are mainly but not exclusively intended to pr0 vide exterior surfaces and are characterized by a series of shallow bends that extend parallel to the opposite marginal sections of the structural member and define, across the width of the panel section, alternating forwardly and rearwardly inclined oblique segments that cooperate to produce an architecturally desirable pattern of light and shadow. The other illustrated panel section configuration, which is mainly but not exclusively intended for interior surfaces, is characterized by being flat across most of its width, but with a medial V-shaped indentation.

It will be apparent that many other types of ornamental treatment of the panel section 11 are possible in the structural member of this invention. However, a great variety of different wall surface patterns can be achieved with the use of structural members having only two different panel configurations, owing to the fact that structural members of this invention are fully interchangeable with one another so that they can be mixed or mached in many different arrangements, as suggested by FIGS. 3 and 4.

Turning now to a more detailed consideration of the structural member 6, which is in itself a very versatile module, its panel section 11 has a pair of oblique segments 19, one adjacent to each of its marginal sections 12 and 13, and each of which oblique segments is inclined rearwardly and laterally outwardly. Hence the marginal sections 12 and 13 of the structural member are spaced to the rear of the major portion of its panel section.

The tongue 14, which comprises a portion of the marginal section 13 of the structural member and is defined by lengthwise extending bends therein, projects laterally outwardly beyond the panel section 11 of the structural mem her. The tongue is generally U-shaped in cross-section, having a front wall 20 that extends laterally outwardly from its adjacent oblique segment 19 of the panel section, an outer wall 21 that extends rearwardly from the front wall 20, and a laterally inwardly extending rear wall 22. Continuous with the rear wall 22 and extending laterally inwardly from it a substantial distance is a connecting wall portion 23 having a rearwardly extending leg 24 at its laterally innermost extremity. The flange 17 projects laterally outwardly from the rearwardly extend ing leg 24.

Note that the width of the flange 17, measured laterally of the structural member, is less than half that of the laterally extending wall 23 of the connecting portion, so that said flange is offset a substantial distance laterally inward from the tongue 14 and lies wholly behind the panel section 11. Attention is also directed to the fact that the flange 17 extends laterally outwardly from the leg 24 of the connecting portion, so there is a substantially wide lateral ly outwardly opening throat or bay 26 between the flange and the laterally extending wall 24 of the connecting portion. Through that bay the front face of the flange 17 is readily accessible anywhere along its length, for the installation of fastening means by which it can be attached to an opposing surface of another structural part.

The laterally outwardly opening groove 15 is defined by lengthwise extending bends in the other marginal section 12. Specifically, the groove defining portions of the marginal section 12 comprise a front wall 28 that extends laterally inwardly from its adjacent oblique segment 19 of the panel section, an inner wall 29 that projects rearwardly from the front wall 28, and a rear wall 30 that extends laterally outwardly from the inner wall 29.

The laterally extending front and rear walls 28 and 30 of the groove portion are somewhat deeper than the laterally extending walls 20 and 22 of the tongue portion, and the inner wall 29 of the groove portion is likewise somewhat deeper than the outer wall 21 of the tongue portion. Hence when structural members of the invention are assembled in interlocked side-by-side relation, the tongue 14 on each structural member has an easy fit in the groove 15 in its adjacent structural member, but it normally does not bottom therein, as explained hereinafter.

From the rear wall 30 of the groove portion a short connecting portion 31 extends rearwardly, and the flange means 16 projects laterally outwardly from it, having about the same width, measured laterally, as the flange 17.

Attention is directed to the fact that the groove portion, comprising the walls 28, 29 and 30, is disposed entirely behind the panel section 11 of the member, and that ll of the flange 16 projects laterally outwardly beyond the panel section.

As best shown in FIG. 4, a group of sheet metal structural members 6 of this invention can be secured in sideby-side interlocked relation to a standing wall 18, with the rear surfaces of the flanges 16 and 17 flatwise engaging the front surface of the wall and with only the flange means 16 at the groove side of each member secured to the wall by nails 33 or the like. It is unnecessary to insert fasteners through the other, somewhat less accessible, flange 17 because that side of each structural member is held against the wall surface by its interlocking connection with its adjacent member. Thus in the arrangement depicted in FIG. 4 the members would be installed in a sequence from right to left.

For purposes of clarity, the several interconnected members 6 shown in FIGS. 3 and 4 are illustrated as slightly separated. Each member has a nose or acute corner 34 at the front of its marginal section 12, which nose is defined by the junction of the front wall 28 of its groove portion with its adjacent oblique segment 19. As the members are actually installed, the nose 34 on each member 6 sealing engages all along its length against its adjacent oblique segment 19 on the neighboring member. The relationship of the fully connected members can be observed in FIG. 2, where it will be observed that the tongues 14, as mentioned above, do not extend laterally outwardly far enough to bottom in the grooves 15, and that the adjacent flanges 16 and 17 of connected members are edgewise spaced from one another, thus insuring the sealing engagement just described.

Attention is directed to the fact that the two marginal sections 12 and 13 of each member 6 are of equal frontto-rear depth. This enables the use of a standardized trim member (not shown) at both the left and right ends of a row of interconnected structural members of this invention.

Two of the structural members 6 can be assembled to produce a curtain wall module by establishing them in generally flatwise opposed relationship, with the rear surface of the flange 16 on each member flatwise opposing the rear surface of the flange 17 on the other, and then securely connecting the opposing flanges.

As best seen in FIG. 1, this connection of the two members 6 disposes their panel sections 11 in laterally offset relationship.

The fasteners 8, which are shown as staples, extend through the opposing flanges and the insulating element 9, which is preferably sandwiched between them, at spaced locations along the length thereof. It will be seen that the laterally outwardly opening bay 26 readily admits a bucking tool to the front surface of the flange 17 for securement of the fasteners 8.

Each of the insulating elements 9 is preferably made of a resilient plastic material having a low coeflicient of thermal conductivity. In addition to a strip-like gasket portion 36, which is confined between the flanges, it can have a tail portion 35, which is laterally inward of the flanges, and a laterally outwardly projecting seal forming portion 37. The tail portion 35, which serves only to facilitate manufacture of the module 5, extends generally at right angles to the gasket portion 34 and hooks around the rearwardly extending leg 24 of the connecting portion to hold the insulating element in place during the preliminary assembly of the module components.

The seal forming portion 37 of the insulating element is offset laterally forwardly from its gasket portion and is adapted to have sealing engagement against the front face of the flange 16 on the structural member of a laterally adjacent module 5. To insure that such engagement will be a snug one, the seal forming portion normally has a rearward and laterally outward inclination so that it en" .gages the flange 16 under resilient bias. To cause it to be cammed from its normally inclined to its seal forming position when the curtain wall modules are assembled with one another, its laterally outermost end portion has a rearwardly and laterally inwardly inclined surface 38, and it has a similarly inclined surface 39 near its junction with the gasket portion. The forwardly offset seal forming portion 37 of course cooperates with the tail portion 35 in holding the insulating element in place during assembly of the module.

Note that at the joint between modules that is illustrated in FIG. 2 the complementary insulating elements 9 are identical with one another. It is also noteworthy that the arrangement of the flanges 16 and 17 of the several structural members 6 at that joint provides adequate space for the seal forming portions 37 of the insulating elements 6 at the joint. Hence insulating elements having seal forming portions of other configurations could be used, if desired, without undue restrictions as to their compactness.

From the foregoing description taken with the accompanying drawings it will be apparent that this invention provides an inexpensive but very versatile structural member capable of being interlockingly assembled with other similar structural members to provide an ornamental and protective facade, and also capable of being readily assembled with another similar structural member to provide a curtain wall module which possesses a number of unique advantages.

What is claimed as my invention is:

1. A sheet metal structural member having a medial panel section and marginal sections that extend rearwardly from the panel section at laterally opposite sides thereof, one of said marginal sections being bent to provide a laterally outwardly projecting tongue portion and the other being bent to provide a laterally outwardly opening groove defining portion laterally opposite the tongue portion, said structural member being characterized by: (A) the tongue portion projecting laterally outwardly beyond the panel section and being rearwardly offset relative to it;

(B) the groove defining portion being disposed behind the panel section; and

(C) laterally outwardly projecting flange means comprising the longitudinal extremities of each of said marginal sections providing rearwardly facing coplanar surfaces adapted to oppose surface portions of a structure to which the member is to be attached, said flange means being laterally opposite one another and spaced rearwardly from the tongue and groove defining portions,

(1) the flange means on the first mentioned marginal section being oflset a substantial distance laterally inwardly from the tongue to be wholly disposed behind the panel section, and

(2) the flange means on said other marginal section projecting laterally beyond the panel section.

2. The structural member of claim 1, in combination with a second similar structural member, further characterized by:

means connecting said structural members with the flange means on the first mentioned marginal section of each structural member flatwise opposing the flange means on said other marginal section of the other,

said connecting means extending through the opposing flange means of the two structural members to unite them in a curtain wall module. 3. The combination of claim 2, further characterized by: an insulating element sandwiched between each opposing pair of flange means to prevent transfer of heat between the two structural members. b 4. The combination of claim 3, further characterized one of said insulating elements having a sealing portion which projects laterally outwardly beyond the flange means between which it is sandwiched and which is adapted to have snug engagement with the front face of adjacent flange means on another similar curtain wall module.

5. A sheet metal structural member bent to have a medial panel section that provides an exposed surface flanked by opposite marginal sections that extend rearwardly therefrom, characterized by:

(A) one of said marginal sections being bent along its length to define (l) a tongue that projects laterally outwardly beyond the panel section and is rearwardly offset relative to it, and

7 (2) laterally outwardly projecting rearwardly facing first flange means offset rearwardly and a substantial distance laterally inwardly from the tongue; and (B) the other of said marginal sections being bent along its length to define (l) a laterally outwardly opening groove laterally opposite the tongue, the groove defining portion of said other marginal section being disposed in substantial part behind the panel section, and (2) second rearwardly facing flange means laterally opposite and coplanar with the first flange means and projecting laterally outwardly beyond the mouth of the groove. 6. In combination with the structural member of claim 5:

(A) a second similar structural member, and (B) means fastening said structural members together with the first flange means on each opposing the second flange means on the other, so that the two structural members cooperate to provide a curtain wall module.

7. Structure providing a joint between a pair of sheet metal facade members, each bent to have a panel section that provides an exposed surface and a marginal section which extends rearwardly from the panel section along one side thereof, said joint structure comprising the marginal sections of said members in contiguous interlocking relationship with one another and holding the panel sections of said members in generally coplanar relationship, and said joint structure being characterized by:

(A) one of said members having its marginal section bent to define (l) a tongue that projects laterally outwardly beyond its panel section and is offset rearwardly relative thereto to be disposed behind the panel section of the other member, and (2) first rearwardly facing flange means projecting edgewise toward the other member and offset rearwardly and a substantial distance laterally inwardly from the tongue so as to be disposed behind the panel section of said one member and edgewise spaced from said other member, and (B) the other of said members having its marginal section bent to define (1) a groove in which said tongue is received, the portion of the marginal section of said other member that defines the groove being disposed in substantial part behind the panel section of said other member, and

(2) second rearwardly facing flange means substantially coplanar with said first flange means, projecting laterally outwardly beyond the mouth of the groove so as to be disposed behind the panel section of said one member, but spaced edgewise from the first flange means.

8. The joint structure of claim 7, further characterized by:

the panel section of each of said members having an oblique segment adjacent to its marginal section that is inclined rearwardly and toward the other member, said oblique segment on the second designated member joining the tongue defining portion of its marginal section along an acute corner that sealingly engages against the oblique segment on the first designated member.

9. Structure providing a joint between a pair of sheet metal facade members, each bent to have a panel section that provides an exposed surface and a marginal section which extends rearwardly from the panel section along one side thereof, said joint comprising the marginal sections of said members in contiguous interlocking relationship with one another and holding the panel sections of said members in generally coplanar relationship, and said joint structure being characterized by:

(A) one of said members having its marginal section bent to define a tongue that is offset rearwardly relative to its panel section and projects laterally outwardly beyond its panel section to be disposed behind the panel section of the other member;

(B) the other of said members having its marginal section bent to define a groove in which said tongue is received, substantially all of the groove defining portions of the last mentioned marginal section being disposed behind the panel section of said other member; and

(C) each of said members having its marginal section terminating in rearwardly facing flange means that project edgewise toward the flange means on the other member, the flange means on said two members being substantially coplanar, edgewise spaced apart, and disposed wholly behind the panel section of said one member in rearwardly spaced and laterally offset relation to the tongue and groove defining portions of said members.

10. A sheet metal structural member bent to have a facade forming panel section and a marginal section which extends rearwardly from the panel section along one side thereof, said structural member being characterized by:

(A) its marginal section being bent along its length to provide a tongue that is rearwardly offset relative to its panel section and projects laterally outwardly beyond its panel section to be receivable in a laterally opening groove in an adjacent structural member; and

(B) said marginal section terminating in laterally out wardly projecting flange means offset to the rear of the tongue and a substantial distance laterally inwardly therefrom to be wholly disposed behind the panel section, said flange means providing a rearwardly facing surface adapted to oppose a surface portion of structure to which the member is to be secured;

(C) said flange means being connected with said tongue (1) a portion of the marginal section that extends laterally inwardly from the tongue and provides a surface continuous with the rear surface of the tongue, said last mentioned portion extending across the flange means in forwardly spaced relation thereto and in rearwardly spaced relation to the panel section, and

(2) another portion of the marginal section that extends rearwardly from the last mentioned portion to the flange means and from which the flange means projects laterally outwardly.

11. Structure providing a joint between a pair of laterally adjacent curtain wall modules, each of which comprises a pair of sheet metal structural members, each bent to have a panel section which defines an exposed face of the module and which is flanked by opposite marginal sections, the marginal sections of each member of a module extending inwardly toward and being connected with those of the other member thereof to dispose the panel sections of said members in opposing spaced apart relationship, said joint comprising adjacent marginal sections of the members comprising one module and the contiguous marginal sections of the members comprising the other module and confining each of the panel sections of one module in side-by-side substantially coplanar relation with a panel section of the other, said joint structure being characterized by:

(A) a flange comprising the extremity of said marginal section of each member comprising each module,

(1) said flanges on the members comprising each module being flatwise opposed and projecting edgewise toward said flanges on the other module, and

(2) said flanges on one module being respectively substantially coplanar with, but edgewise spaced from, said flanges on the other module;

(B) said marginal sections of two of the members at the joint which are at outwardly opposite sides of said flanges each being formed to provide (1) a connecting portion which extends outwardly from the flange on the member and thence sidewardly across all of said flanges, in outwardly spaced relation to them, and which is spaced inwardly from the panel section of the member, and

(2) a tongue between said connecting portion and the panel section of the member, projecting sidewardly beyond said panel section and in rearwardly offset relation thereto to be disposed behind the panel section of the sidewardly adjacent member of the other module; and

(C) said marginal sections of the other two members at the joint which are at outwardly opposite sides of said flanges each providing (1) a portion which is behind the panel section of the member and which defines a sidewardly opening groove in which one of said tongues is received, and

(2) a connecting portion extending outwardly from the flange on the member to said groove defining portion thereon.

12. The joint structure of claim 11, further characterized by:

an insulating gasket sandwiched between the flatwise opposed flanges on the members comprising each module.

'13. The joint structure of claim 12, further characterized by:

a sealing element projecting sidewardly from the insulating gasket between one pair of flatwise opposed flanges on one module and in outwardly offset relation to said gasket, said sealing element snugly engaging the outer face of one of its adjacent flatwise opposed flanges on the other module.

14. A wall forming module comprising a pair of sheet metal members, each bent to have a panel section which provides an exposed face of the module, flanked by marginal sections which extend inwardly toward and are connected with the marginal sections of the other member and which cooperate to provide interlock means at opposite sides of the module by which it is connectable with other similar modules, said module being characterized by:

(A) the sheet metal members comprising the module being substantially identical with one another;

(B) the panel sections of said members being flatwise opposed and spaced apart but partially in sidewardly offset relation to one another so that a portion of each projects sidewardly beyond the other;

(C) the marginal section of each member that is adjacent to said projecting portion of its panel section being bent along the length thereof to define a tongue that is offset inwardly relative to its panel section and projects sidewardly beyond its panel section;

(D) a portion of the other marginal section of each member being bent to form a sidewardly outwardly opening groove that is laterally opposite the tongue and disposed between the panel sections of both members; and

(E) the extremities of the adjacent marginal sections of the two members comprising connected, flatwise opposed, sidewardly outwardly projecting flanges that are spaced inwardly from both the tongue and the groove portion, project sidewardly outwardly beyond the mouth of the groove, and have their outer edges spaced sidewardly inwardly a substantial distance from the tongue.

15. A wall forming module comprising a pair of sheet metal members, each bent to have a panel section which provides an exposed face of the module and a marginal section along one side of the panel section which projects inwardly therefrom and is connected with the marginal section of the other member to hold the members with their panel sections in flatwise opposed spaced apart relation, with their marginal sections providing for interlocking connection with a sidewardly adjacent complementary module, said module being characterized by:

(A) the panel section of one of said members projecting sidewardly a distance beyond the panel section of the other;

(B) the marginal section of said one member providing a tongue which projects sidewardly beyond its panel section and is offset inwardly thereof;

(C) a portion of the marginal section of said other member providing a sidewardly outwardly opening groove, said groove defining portion being wholly disposed between the panel sections of the two members; and

(D) the marginal sections of the two members terminating in connected, flatwise opposed, sidewardly outwardly projecting flange means, said flange means being in inwardly offset relation to both the tongue and the groove defining portion, and projecting sidewardly beyond the panel section of said other member but having their outer edges offset a substantial distance sidewardly inwardly from the tongue so as to be wholly disposed behind the panel section of said one member.

16. The wall forming module of claim 15, further characterized by:

the marginal section of said member having (1) a portion which extends sidewardly inwardly from the tongue and has a surface which forms a continuation of the inner surface of the tongue, said portion being in outwardly spaced relation to the flange means on said marginal section, and (2) a portion which extends inwardly from the last mentioned portion and from which said flange means projects sidewardly outwardly, said portions defining a sidewardly outwardly opening space through which said flange means is accessible for securement of fasteners connecting it with the flange means on said other member.

References Cited UNITED STATES PATENTS 973,622 11/1910 Budd 52506 1,706,924 3/1929 Kane 52-542X 1,913,342 6/1933 Schaffert 52-492 2,620,906 12/ 1952 Ketchum 52-529X 3,304,680 2/1967 Birdwell 52588 3,353,318 11/1967 Bacher 52593X FOREIGN PATENTS 641,946 1950 Great Britain 52-588 JOHN E. MURTAGH, Primary Examiner U.S. C1.X.R. 

